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Carbon Energy 2023年第10期5卷 25-39页

作者： Madagonda MVadiyar Ji‐Young Kim Jee‐Hwan Bae kyung‐wan nam Department of Energy and Materials Engineering Dongguk UniversitySeoulSouth Korea Advanced Analysis&Data Center Korea Institute of Science and Technology(KIST)SeoulSouth Korea Advanced Energy and Electronic Materials Research Center Dongguk UniversitySeoulSouth Korea

Carbon super-heterostructures with high nitrogen contents from the covalent hybrid precursors of covalent triazine frameworks(CTFs)and zeolitic imidazolic frameworks(ZIFs)are scarcely explored because of CTF's ordered structure and toxic superacid that dissolves or destabilizes the metal *** solve this problem,herein,we report a straightforward two-step pathway for the covalent hybridization of disordered CTF(d–CTF)–ZIF composites via preincorporation of an imidazole(IM)linker into ordered CTFs,followed by the imidazole-site-specific covalent growth of *** carbonization of these synthesized d–CTF−IM−ZIF hybrids results in unique hollow carbon super-heterostructures with ultrahigh nitrogen content(>18.6%),high specific surface area(1663m^(2)g^(−1)),and beneficial trace metal(Co/Zn NPs)contents for promoting the redox *** proof of concept,the obtained carbon super-heterostructure(Co–Zn–NC_(SNH)–800)is used as a positive electrode in an asymmetric supercapacitor,demonstrating a remarkable energy density of 61Wh kg^(−1)and extraordinary cyclic stability of 97%retention after 30,000 cycles at the cell *** presynthetic modifications of CTF and their covalent hybridization with ZIF crystals pave the way toward new design strategies for synthesizing functional porous carbon materials for promising energy applications.

关键词： asymmetric supercapacitor defective covalent triazine frameworks hollow carbon superheterostructures linker defect

Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

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Nano Research 2015年第1期8卷 117-128页

作者： Ya You Xiqian Yu Yaxia Yin kyung-wan nam Yu-Guo Guo CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences (CAS) Beijing 100190 Chino Chemistry Department Brookhaven National Laboratory Upton New York 11973 USA Department of Energy and Materials Engineering Dongguk University Seoul 100-715 Republic of Korea

Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large- scale grids. Increasing the Na content in cathode materials is one of the effective ways to achieve high energy density. Prussian blue and its analogues （PBAs） are promising Na-rich cathode materials since they can theoretically store two Na＋ ions per formula unit. However, increasing the Na content in PBAs cathode materials remains a major challenge. Here we show that sodium iron hexacyanoferrate with high Na content can be obtained by simply controlling the reducing agent and reaction atmosphere during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mAh·g^-1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/ de-intercalation mechanism has been systematically studied by in situ Raman spectroscopy, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. The Na-rich sodium iron hexacyanoferrate can function as a plenteous Na reservoir and has great potential as a cathode material for practical Na-ion batteries.

关键词： sodium iron hexacyanoferrate Na-rich cathode sodium-ion batteries Prussian blue analogues

Prominent cycling reversibility and kinetics enabled by CaTiO3 protective layer on Zn metal for aqueous Zn-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 245-258页

作者： Gaeun Lee Yong nam Ahn Seongjoon So Chanwoo Park Jong-Seong Bae Taehyun Park Il Tae Kim Jaehyun Hur School of Chemical Biological and Battery Engineering Gachon University Seongnam Busan Center Korea Basic Science Institute

Aqueous Zn-ion batteries （AZIBs） have received considerable attention owing to their various advantages such as safety,low cost,simple battery assembly conditions,and high ionic ***,they still suffer from serious problems,including uncontrollable dendrite growth,corrosion,hydrogen evolution reaction （HER） from water decomposition,electrode passivation,and unexpected *** creation of a uniform artificial nanocrystal layer on the Zn anode surface is a promising strategy for resolving these ***,we propose the use of a perovskite CaTiO3（CTO） protective layer on Zn（CTO@Zn） as a promising approach for improving the performance of *** CTO artificial layer provides an efficient pathway for Zn ion diffusion towards the Zn metal because of the high dielectric constant （εr=180） and ferroelectric characteristics that enable the alignment of dipole moments and redistribute the Zn2+ions in the CTO *** avoiding the direct contact of the Zn anode with the electrolyte solution,the uneven dendrite growth,corrosion,parasitic side reactions,and HER are mitigated,while CTO retains its mechanical and chemical robustness during ***,CTO@Zn demonstrates an improved lifespan in a symmetric cell configuration compared with bare ***@Zn shows steady overpotential （～68 m V） for 1500 h at 1 mA cm-2/0.5 mA h cm-2,excelling bare ***,when paired with the V2O5-C cathode,the CTO@Zn//V2O5-C full battery delivers 148.4 mA h g-1（based on the mass of the cathode） after 300 *** study provides new insights into Zn metal anodes and the development of high-performance AZIBs.

关键词： Artificial layer Dielectric constant Zn metal anode Zinc aqueous battery

A Rapid Adaptation Approach for Dynamic Air‑Writing Recognition Using Wearable Wristbands with Self‑Supervised Contrastive Learning

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Nano-Micro Letters 2025年第2期17卷 417-431页

作者： Yunjian Guo Kunpeng Li Wei Yue nam‑Young Kim Yang Li Guozhen Shen Jong‑Chul Lee Department of Electronic Convergence Engineering Kwangwoon UniversitySeoul 01897South Korea Radio Frequency Integrated Circuit(RFIC)Bio Centre Kwangwoon UniversitySeoul 01897South Korea Department of Electronic Engineering Kwangwoon UniversitySeoul 01897South Korea School of Microelectronics Shandong UniversityJinan 250101People’s Republic of China State Key Laboratory of Integrated Chips and Systems Fudan UniversityShanghai 200433People’s Republic of China School of Integrated Circuits and Electronics Beijing Institute of TechnologyBeijing 100081People’s Republic of China

Wearable wristband systems leverage deep learning to revolutionize hand gesture recognition in daily *** existing approaches that often focus on static gestures and require extensive labeled data,the proposed wearable wristband with selfsupervised contrastive learning excels at dynamic motion tracking and adapts rapidly across multiple *** features a four-channel sensing array composed of an ionic hydrogel with hierarchical microcone structures and ultrathin flexible electrodes,resulting in high-sensitivity capacitance *** wireless transmission from a Wi-Fi module,the proposed algorithm learns latent features from the unlabeled signals of random wrist ***,only few-shot labeled data are sufficient for fine-tuning the model,enabling rapid adaptation to various *** system achieves a high accuracy of 94.9%in different scenarios,including the prediction of eight-direction commands,and air-writing of all numbers and *** proposed method facilitates smooth transitions between multiple tasks without the need for modifying the structure or undergoing extensive task-specific *** utility has been further extended to enhance human–machine interaction over digital platforms,such as game controls,calculators,and three-language login systems,offering users a natural and intuitive way of communication.

关键词： Wearable wristband Self-supervised contrastive learning Dynamic gesture Air-writing Human-machine interaction

Spatio-temporal variability in sea surface wind stress near and off the east coast of Korea

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Acta Oceanologica Sinica 2005年第1期24卷 107-114页

作者： nam SungHyun KIM Young Ho PARK kyung-Ae KIM Kuh Ocean Laboratory/RIO School of Earth and Environmental Sciences Seoul National University Seoul 151-742 KoreaOcean Laboratory/RIO School of Earth and Environmental Sciences Seoul National University Seoul 151-742 KoreaOcean Laboratory/RIO School of Earth and Environmental Sciences Seoul National University Seoul 151-742 KoreaOcean Laboratory/RIO School of Earth and Environmental Sciences Seoul National University Seoul 151-742 Korea

Sea surface wind stress variabilities near and off the east coast of Korea, are examined using 7 kinds of wind datasets from measurements at 2 coastal (land) stations and 2 ocean buoys,satellite scatterometer (QuikSCAT), and global reanalyzed products (ECMWF,NOGAPS,and NCEP/NCAR). Temporal variabilities are analyzed at 3 frequency bands; synoptic (2-20 d), intra-seasonal (20-90 d),and seasonal (>90 d).Synoptic and intra-seasonal variations are predominant near and off the Donghae City due to the passage of the mesoscale weather system. Seasonal variation is caused by southeastward wind stress during Asian winter monsoon. The sea surface wind stress from reanalyzed *** and KMA-B measurements off the coast show good agreement in the magnitude and direction,which are strongly aligned with the alongshore *** the land-based sites,wind stresses are much weaker by factors of 3-10 due to the mountainous landmass on the east parts of Korea *** first EOF modes(67%-70%) of wind stresses from reanalyzed and QuikSCAT data have similar structures of the strong southeastward wind stress in winter along the coast but show different curl structures at scales less than 200 km due to the orographic *** second EOF modes (23%-25%) show southwestward wind stress in every September along the east coast of the North Korea

关键词： sea surface wind stress spatio-temporal variability monsoon seasonal intra-seasonal synoptic band orographic effect

Dynamic modeling and analysis of vortex filament motion using a novel curve-fitting method

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Chinese Journal of Aeronautics 2016年第1期29卷 53-65页

作者： Chang-Joo Kim Soo Hyung Park Sang kyung Sung Sung-nam Jung Department of Aerospace Information Engineering Konkuk UniversitySeoul 05029Republic of Korea

Applications of a novel curve-fitting technique are presented to efficiently predict the motion of the vortex filament, which is trailed from a rigid body such as wings and rotors. The gov- erning equations of the motion, when a Lagrangian approach with the present curve-fitting method is applied, can be transformed into an easily solvable form of the system of nonlinear ordinary dif- ferential equations. The applicability of Bezier curves, B-spline, and Lagrange interpolating polyno- mials is investigated. Local Lagrange interpolating polynomials with a shift operator are proposed as the best selection for applications, since it provides superior system characteristics with minimum computing time, compared to other methods. In addition, the Gauss quadrature formula with local refinement strategy has been developed for an accurate prediction of the induced velocity computed with the line integration of the Biot-Savart law. Rotary-wing problems including a vortex ring problem are analyzed to show the efficiency, accuracy, and flexibility in the applications of the pro- posed method.

关键词： Aerodynamics Biot-Savart law Curve-fitting method Free-vortex wake Rotary wing Vortex filament

Sandwich-structure transferable free-form OLEDs for wearable and disposable skin wound photomedicine

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Light(Science & Applications) 2019年第1期8卷 96-110页

作者： Yongmin Jeon Hye-Ryung Choi Jeong Hyun Kwon Seungyeop Choi kyung Mi nam Kyoung-Chan Park kyung Cheol Choi School of Electrical Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea Department of Dermatology Seoul National University Bundang Hospital(SNUBH)Seongnam 13620Republic of Korea

Free-form optoelectronic devices can provide hyper-connectivity over space and ***,most conformable optoelectronic devices can only be fabricated on flat polymeric materials using low-temperature processes,limiting their application and *** paper presents free-form optoelectronic devices that are not dependent on the shape or *** medical applications,the transferable OLED(10μm)is formed in a sandwich structure with an ultra-thin transferable barrier(4.8μm).The results showed that the fabricated sandwich-structure transferable OLED(STOLED)exhibit the same high-efficiency performance on cylindricalshaped materials and on materials such as textile and *** the neutral axis is freely adjustable using the sandwich structure,the textile-based OLED achieved both folding reliability and washing reliability,as well as a long operating life(>150 h).When keratinocytes were irradiated with red STOLED light,cell proliferation and cell migration increased by 26 and 32%,*** the skin equivalent model,the epidermis thickness was increased by 39%;additionally,in organ culture,not only was the skin area increased by 14%,but also,reepithelialization was highly *** on the results,the STOLED is expected to be applicable in various wearable and disposable photomedical devices.

关键词： optoelectronic structure transfer

Laparoscopic uncontained power morcellation-induced dissemination of ovarian endodermal sinus tumors:A case report

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World Journal of Clinical Cases 2021年第13期9卷 3212-3218页

作者： Ha kyung Oh Seong nam Park Byoung Ryun Kim Department of Obstetrics and Gynecology Wonkwang University HospitalIksan 54645Jeollabuk-doSouth Korea

BACKGROUND Endodermal sinus tumors(ESTs),which arise primarily in children and adolescents,account for 20%of malignant ovarian germ cell tumors,but constitute only 1%of all ovarian *** of ESTs consists of surgical staging with fertility-sparing surgery and *** SUMMARY A 15-year-old nulliparous patient was diagnosed with disseminated ovarian ESTs after laparoscopic unilateral salpingo-oophorectomy using uncontained power morcellation for treatment of a ruptured solid adnexal mass in another *** laparotomy;total abdominal hysterectomy,right salpingooophorectomy,and lymphadenectomy were performed with optimal debulking,and surgical stage 3C was assigned to the *** In 2014,the Food and Drug Administration noted that power morcellation was probably associated with a risk of disseminating suspected cancerous ***,the use of power morcellation to remove solid adnexal mass is considered a contraindication because of the potential for a malignant *** case report aims to warn of the dangers of using uncontained power morcellation to treat solid adnexal masses.

关键词： Dissemination Endodermal sinus tumor Morcellation Yolk sac tumor Case report

A Unified Buffering Management with Set Divisible Cache for PCM Main Memory

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Journal of Computer Science & Technology 2016年第1期31卷 137-146页

作者： Mei-Ying Bian Su-kyung Yoon Jeong-Geun Kim Sangjae nam Shin-Dug Kim Department of Computer Science Yonsei University Seoul 120-749 Korea

This research proposes a phase-change memory （PCM） based main memory system with an effective combi- nation of a superblock-based adaptive buffering structure and its associated set divisible last-level cache （LLC）. To achieve high performance similar to that of dynamic random-access memory （DRAM） based main memory, the superblock-based adaptive buffer （SABU） is comprised of dual DRAM buffers, i.e., an aggressive superblock-based pre-fetching buffer （SBPB） and an adaptive sub-block reusing buffer （SBRB）, and a set divisible LLC based on a cache space optimization scheme. According to our experiment, the longer PCM access latency can typically be hidden using our proposed SABU, which can significantly reduce the number of writes over the PCM main memory by 26.44%. The SABU approach can reduce PCM access latency up to 0.43 times, compared with conventional DRAM main memory. Meanwhile, the average memory energy consumption can be reduced by 19.7%.

关键词： memory hierarchy memory structure,cache memory buffer management

Aging Behavior of Mg-Y-Zr and Mg-Nd-Zr Cast Alloys

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Journal of Materials Science & Technology 2008年第1期24卷 80-84页

作者： Yang-Do Kim nam-Hyun Kang Il-Guk Jo kyung-Hyun Kim In-Bae Kim School of Materials Science and Engineering Pusan National University 30 Jangjun-dongGeumjeong-guBusan 609-735Korea Deptartment of Materials Engineering Korea Institute of Machinery & Materials 66 Sangnam-dongChangwonGyeongsangnam-do 641-010Korea

Aging behavior of Mg-3.6Y-0.5Zr and ***-0.5Zr alloys was investigated by microhardness measurement and transmission electron *** the case of Mg-Y-Zr alloy,the presence ofβ″phase,a major strength- ener,having base centered orthorhombic structure with its lattice constants of a-（β″）=0.64 nm,b-（β″）=2.22 nm, and c-（β″）=0.52 nm was *** the case of Mg-Nd-Zr alloy aged at 250℃,the presence ofβ″andβ′phases was *** crystal structure ofβ″phase was found to be DO-（19） and its orientation relationships with Mg matrix were [0001]-（β″）//[0001]-（Mg） and [01（？）0]-（β″）//[01（？）0]-（Mg）.Theβ′phase had face centered cubic structure and its orientation relationships with Mg matrix were [011]-（β′）//[0001]-（Mg） and [（？）1（？）]β′//[（？）110]）-（Mg）. The ***-0.5Zr alloy showed higher hardness compared with Mg-3.6Y-0.5Zr alloy.

关键词： Mg-Y-Zr alloy Mg-Nd-Zr alloy Precipitation sequence